Resistance to antibiotics is more common in southern and eastern Europe than in northern Europe, because the regions have high rates of antibiotic use, suggests a study published in this week’s issue of The Lancet.

Herman Goossens of the University of Antwerp, Belgium, and colleagues compared antibiotic use with antibiotic resistance rates in 26 European countries from the beginning of 1997 to the end of 2002. To control for the different population sizes, the investigators expressed data in defined daily dose per 1,000 inhabitants daily (DID).

Regional, Seasonal Differences

The study found that the prescription of antibiotics in primary care in Europe vary greatly. The highest rate was in France (32·2 DID) and the lowest was in the Netherlands (10·0 DID). Across Europe, antibiotic use was lower in northern, moderate in eastern and higher in southern regions.

Seasonal fluctuations were high in southern and eastern European countries, whereas in northern European countries, the increase in antibiotic use during the winter was less than 25%. In most countries, the researchers found a growing use of the newer antibiotics (active against a broad spectrum of micro-organisms) and a decline in use of the older antibiotics (active against a narrow spectrum of micro-organisms).

The authors believe the data will be useful for assessing public health strategies that aim to reduce inappropriate antibiotic use and resistance levels. The differences in antibiotic use between countries might be explained by variations in incidence of community infections, culture and education, as well as differences in drug relations and in the structure of the national pharmaceutical market, they write.

Miracle Drugs Could Be Lost

“Population-based studies are needed to determine the motivation and incentives that lead individuals to use or not to use antibiotics," Professor Goossens recommends.

"The ethics of promoting antibiotics in clinical situations in which they are unnecessary should be given serious consideration," he says. "In view of the emergence of bacterial resistance and the decline in the rate of development of novel antibiotics, effective professional and public strategies to encourage appropriate prescribing of antibiotics should be studied and implemented. If not, we will lose the miracle drugs of the 20th century.”

The method used by Goossens and colleagues to correlate antimicrobial use with resistance has been effective but crude, John Turnidge of Women’s and Children’s Hospital, North Adelaide, Australia, and Keryn Christiansen of Royal Perth Hospital, Perth, Australia, state in an accompanying commentary.

“If we develop more sophisticated systems to measure antimicrobial use that incorporate the many influences -- such as the proportion of individuals exposed, the proportion of children in the population, population densities, the effects of different drug classes, and the differences between bacterial species -- it will help us to design and measure the success of intervention strategies,” says Professor Turnidge.